Well, the game developers did actually:"How historically accurate will 0 A.D. be?As much as we can make it. Our dedicated historians oversee all of our content to ensure it's historically accurate. Ancient history is a rich resource to exploit, and we hope to promote greater interest in it. However, there are various factors we have to take into account that won't allow us pure realism and authenticity:"(insert obvious things related to this being a game).

Which still makes "0 A.D." a silly thing to find requiring an ego-destroying suspension of disbelief. I think it works perfectly to both establish the game's period in history, and to designate that it is still outside of that history and somewhat fantastical as a game requires. The name works by assuming you are aware that the date does not exist, rather than assuming ignorance.

Nor was it ever AD 1 in any sense other than retroactively. Wednesday, the 28th of August, Diocletian 247 was immediately followed by Thursday, the 1st of January, AD 532. (The Diocletian calendar started with August 29.)

Retroactively, 1 AD, the 1st of January was a Saturday, so the last day of BCE was a Friday. TGIF! (cal 1 1)

Determining what calendaring systems were observed contemporaneously with our CE 1/1/1 and the corresponding dates thereto is left as an exercise for archæochronologists.

The only reason there wasn't a year "0 A.D." is because the people who created the calendars back then weren't as smart as you are and didn't fully understand the concept of zero-offsets

Actually, retroactively re-dating the dates before AD 1 wasn't considered until the Anglo-Saxon historian the Venerable Bede, who was familiar with the work of Dionysius, used Anno Domini dating in his Ecclesiastical History of the English People, finished in 731. In this same history he also used another Latin term, "ante vero incarnationis dominicae tempus" ("the time before the Lord's true incarnation"), equivalent to the English "before Christ", to identify years before the first year of this era, thus establishing the standard of not using a year zero (i.e. ordinal, not cardinal numbers), even though his work did show that he did grasp the concept of zero.